﻿// Copyright 2009-2024 Josh Close
// This file is a part of CsvHelper and is dual licensed under MS-PL and Apache 2.0.
// See LICENSE.txt for details or visit http://www.opensource.org/licenses/ms-pl.html for MS-PL and http://opensource.org/licenses/Apache-2.0 for Apache 2.0.
// https://github.com/JoshClose/CsvHelper
using CsvHelper.TypeConversion;
using System.Collections;
using System.Linq.Expressions;

namespace CsvHelper.Configuration;

/// <summary>
/// Has mapping capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
public interface IHasMap<TClass> : IBuildableClass<TClass>
{
	/// <summary>
	/// Maps a member to a CSV field.
	/// </summary>
	/// <param name="expression">The member to map.</param>
	/// <param name="useExistingMap">If true, an existing map will be used if available.
	/// If false, a new map is created for the same member.</param>
	/// <returns>The member mapping.</returns>
	IHasMapOptions<TClass, TMember> Map<TMember>(Expression<Func<TClass, TMember?>> expression, bool useExistingMap = true);
}

/// <summary>
/// Options after a mapping call.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasMapOptions<TClass, TMember> :
	IHasMap<TClass>,
	IHasTypeConverter<TClass, TMember>,
	IHasIndex<TClass, TMember>,
	IHasName<TClass, TMember>,
	IHasOptional<TClass, TMember>,
	IHasConvertUsing<TClass, TMember>,
	IHasDefault<TClass, TMember>,
	IHasConstant<TClass, TMember>,
	IHasValidate<TClass, TMember>
{ }

/// <summary>
/// Has type converter capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasTypeConverter<TClass, TMember> : IBuildableClass<TClass>
{
	/// <summary>
	/// Specifies the <see cref="TypeConverter"/> to use
	/// when converting the member to and from a CSV field.
	/// </summary>
	/// <param name="typeConverter">The TypeConverter to use.</param>
	IHasTypeConverterOptions<TClass, TMember> TypeConverter(ITypeConverter typeConverter);

	/// <summary>
	/// Specifies the <see cref="TypeConverter"/> to use
	/// when converting the member to and from a CSV field.
	/// </summary>
	/// <typeparam name="TConverter">The <see cref="System.Type"/> of the 
	/// <see cref="TypeConverter"/> to use.</typeparam>
	IHasTypeConverterOptions<TClass, TMember> TypeConverter<TConverter>() where TConverter : ITypeConverter;
}

/// <summary>
/// Options after a type converter call.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasTypeConverterOptions<TClass, TMember> :
	IHasMap<TClass>,
	IHasDefault<TClass, TMember>,
	IHasValidate<TClass, TMember>
{ }

/// <summary>
/// Has index capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasIndex<TClass, TMember> : IBuildableClass<TClass>
{
	/// <summary>
	/// When reading, is used to get the field at
	/// the given index. When writing, the fields
	/// will be written in the order of the field
	/// indexes.
	/// </summary>
	/// <param name="index">The index of the CSV field.</param>
	/// <param name="indexEnd">The end index used when mapping to an <see cref="IEnumerable"/> member.</param>
	IHasIndexOptions<TClass, TMember> Index(int index, int indexEnd = -1);
}

/// <summary>
/// Options after an index call.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasIndexOptions<TClass, TMember> :
	IHasMap<TClass>,
	IHasTypeConverter<TClass, TMember>,
	IHasName<TClass, TMember>,
	IHasDefault<TClass, TMember>,
	IHasValidate<TClass, TMember>
{ }

/// <summary>
/// Has optional capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasOptional<TClass, TMember> : IBuildableClass<TClass>
{
	/// <summary>
	/// Ignore the member when reading if no matching field name can be found.
	/// </summary>
	IHasOptionalOptions<TClass, TMember> Optional();
}

/// <summary>
/// Options after an optional call.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasOptionalOptions<TClass, TMember> :
	IHasMap<TClass>,
	IHasTypeConverter<TClass, TMember>,
	IHasName<TClass, TMember>,
	IHasDefault<TClass, TMember>,
	IHasValidate<TClass, TMember>
{ }

/// <summary>
/// Has name capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasName<TClass, TMember> : IBuildableClass<TClass>
{
	/// <summary>
	/// When reading, is used to get the field
	/// at the index of the name if there was a
	/// header specified. It will look for the
	/// first name match in the order listed.
	/// When writing, sets the name of the 
	/// field in the header record.
	/// The first name will be used.
	/// </summary>
	/// <param name="names">The possible names of the CSV field.</param>
	IHasNameOptions<TClass, TMember> Name(params string[] names);
}

/// <summary>
/// Options after a name call.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasNameOptions<TClass, TMember> :
	IHasMap<TClass>,
	IHasTypeConverter<TClass, TMember>,
	IHasNameIndex<TClass, TMember>,
	IHasDefault<TClass, TMember>,
	IHasValidate<TClass, TMember>
{ }

/// <summary>
/// Has name index capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasNameIndex<TClass, TMember> : IBuildableClass<TClass>
{
	/// <summary>
	/// When reading, is used to get the 
	/// index of the name used when there 
	/// are multiple names that are the same.
	/// </summary>
	/// <param name="index">The index of the name.</param>
	IHasNameIndexOptions<TClass, TMember> NameIndex(int index);
}

/// <summary>
/// Options after a name index call.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasNameIndexOptions<TClass, TMember> :
	IHasMap<TClass>,
	IHasTypeConverter<TClass, TMember>,
	IHasDefault<TClass, TMember>,
	IHasValidate<TClass, TMember>
{ }

/// <summary>
/// Has convert using capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasConvertUsing<TClass, TMember> : IBuildableClass<TClass>
{
	/// <summary>
	/// Specifies an expression to be used to convert data in the
	/// row to the member.
	/// </summary>
	/// <param name="convertExpression">The convert expression.</param>
	IHasMap<TClass> ConvertUsing(ConvertFromString<TMember> convertExpression);

	/// <summary>
	/// Specifies an expression to be used to convert the object
	/// to a field.
	/// </summary>
	/// <param name="convertExpression">The convert expression.</param>
	IHasMap<TClass> ConvertUsing(ConvertToString<TClass> convertExpression);
}

/// <summary>
/// Has default capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasDefault<TClass, TMember> : IBuildableClass<TClass>
{
	/// <summary>
	/// The default value that will be used when reading when
	/// the CSV field is empty.
	/// </summary>
	/// <param name="defaultValue">The default value.</param>
	IHasDefaultOptions<TClass, TMember> Default(TMember defaultValue);

	/// <summary>
	/// The default value that will be used when reading when
	/// the CSV field is empty. This value is not type checked
	/// and will use a <see cref="ITypeConverter"/> to convert
	/// the field. This could potentially have runtime errors.
	/// </summary>
	/// <param name="defaultValue">The default value.</param>
	IHasDefaultOptions<TClass, TMember> Default(string defaultValue);
}

/// <summary>
/// Options after a default call.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasDefaultOptions<TClass, TMember> :
	IHasMap<TClass>,
	IHasValidate<TClass, TMember>
{ }

/// <summary>
/// Has constant capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasConstant<TClass, TMember> : IBuildableClass<TClass>
{
	/// <summary>
	/// The constant value that will be used for every record when 
	/// reading and writing. This value will always be used no matter 
	/// what other mapping configurations are specified.
	/// </summary>
	/// <param name="value">The constant value.</param>
	IHasMap<TClass> Constant(TMember value);
}

/// <summary>
/// Has validate capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
/// <typeparam name="TMember">The member type.</typeparam>
public interface IHasValidate<TClass, TMember> : IBuildableClass<TClass>
{
	/// <summary>
	/// The validate expression that will be called on every field when reading.
	/// The expression should return true if the field is valid.
	/// If false is returned, a <see cref="ValidationException"/>
	/// will be thrown.
	/// </summary>
	/// <param name="validateExpression">The validation expression.</param>
	IHasMap<TClass> Validate(Validate validateExpression);
}

/// <summary>
/// Has build capabilities.
/// </summary>
/// <typeparam name="TClass">The class type.</typeparam>
public interface IBuildableClass<TClass>
{
	/// <summary>
	/// Builds the <see cref="ClassMap{TClass}"/>.
	/// </summary>
	ClassMap<TClass> Build();
}

internal class ClassMapBuilder<TClass> : IHasMap<TClass>
{
	private readonly ClassMap<TClass> map;

	public ClassMapBuilder()
	{
		map = new BuilderClassMap<TClass>();
	}

	public IHasMapOptions<TClass, TMember> Map<TMember>(Expression<Func<TClass, TMember?>> expression, bool useExistingMap = true)
	{
		return new MemberMapBuilder<TClass, TMember>(map, map.Map(expression, useExistingMap));
	}

	public ClassMap<TClass> Build()
	{
		return map;
	}

	private class BuilderClassMap<T> : ClassMap<T> { }
}

internal class MemberMapBuilder<TClass, TMember> :
	IHasMap<TClass>,
	IHasMapOptions<TClass, TMember>,
	IHasTypeConverter<TClass, TMember>,
	IHasTypeConverterOptions<TClass, TMember>,
	IHasIndex<TClass, TMember>,
	IHasIndexOptions<TClass, TMember>,
	IHasName<TClass, TMember>,
	IHasNameOptions<TClass, TMember>,
	IHasNameIndex<TClass, TMember>,
	IHasNameIndexOptions<TClass, TMember>,
	IHasOptional<TClass, TMember>,
	IHasOptionalOptions<TClass, TMember>,
	IHasConvertUsing<TClass, TMember>,
	IHasDefault<TClass, TMember>,
	IHasDefaultOptions<TClass, TMember>,
	IHasConstant<TClass, TMember>,
	IHasValidate<TClass, TMember>
{
	private readonly ClassMap<TClass> classMap;
	private readonly MemberMap<TClass, TMember> memberMap;

	public MemberMapBuilder(ClassMap<TClass> classMap, MemberMap<TClass, TMember> memberMap)
	{
		this.classMap = classMap;
		this.memberMap = memberMap;
	}

#pragma warning disable CS0693 // Type parameter has the same name as the type parameter from outer type
	public IHasMapOptions<TClass, TMember> Map<TMember>(Expression<Func<TClass, TMember?>> expression, bool useExistingMap = true)
	{
		return new MemberMapBuilder<TClass, TMember>(classMap, classMap.Map(expression, useExistingMap));
	}
#pragma warning restore CS0693 // Type parameter has the same name as the type parameter from outer type

	public IHasMap<TClass> ConvertUsing(ConvertFromString<TMember> convertExpression)
	{
		memberMap.Convert(convertExpression);
		return this;
	}

	public IHasMap<TClass> ConvertUsing(ConvertToString<TClass> convertExpression)
	{
		memberMap.Convert(convertExpression);
		return this;
	}

	public IHasDefaultOptions<TClass, TMember> Default(TMember defaultValue)
	{
		memberMap.Default(defaultValue);
		return this;
	}

	public IHasDefaultOptions<TClass, TMember> Default(string defaultValue)
	{
		memberMap.Default(defaultValue);
		return this;
	}

	public IHasIndexOptions<TClass, TMember> Index(int index, int indexEnd = -1)
	{
		memberMap.Index(index, indexEnd);
		return this;
	}

	public IHasNameOptions<TClass, TMember> Name(params string[] names)
	{
		memberMap.Name(names);
		return this;
	}

	public IHasNameIndexOptions<TClass, TMember> NameIndex(int index)
	{
		memberMap.NameIndex(index);
		return this;
	}

	public IHasOptionalOptions<TClass, TMember> Optional()
	{
		memberMap.Optional();
		return this;
	}

	public IHasTypeConverterOptions<TClass, TMember> TypeConverter(ITypeConverter typeConverter)
	{
		memberMap.TypeConverter(typeConverter);
		return this;
	}

	public IHasTypeConverterOptions<TClass, TMember> TypeConverter<TConverter>() where TConverter : ITypeConverter
	{
		memberMap.TypeConverter<TConverter>();
		return this;
	}

	public IHasMap<TClass> Constant(TMember value)
	{
		memberMap.Constant(value);
		return this;
	}

	public IHasMap<TClass> Validate(Validate validateExpression)
	{
		memberMap.Validate(validateExpression);
		return this;
	}

	public ClassMap<TClass> Build()
	{
		return classMap;
	}
}
